Digital mapping is a technique whereby map data is compiled and rendered to form a virtual image of a map for display on a screen of a computer, mobile device, GPS navigation unit or the like. Map applications typically enable searching for addresses, points of interest, commercial establishments, or other labeled features. Map applications typically also enable panning and zooming.
When a user wishes to view in greater detail an onscreen map location associated with a search result, a specific map feature, a point of interest, an intersection or any other portion of the map, the user must magnify the map. There is typically a lag as additional map data is downloaded and rendered. This lag is most noticeable on mobile devices because the device must request and receive the additional map data over the air. Even when the additional map data is already cached on the device, there is some lag due to the time required to render the new map.
In addition to the lag, there is a loss of general context associated with magnification. In other words, by zooming in on the feature, the user loses the overview of the map area. The user thus typically spends an undesirable amount of time zooming in on a feature and then zooming out to regain a sense of context and overview. For example, this is a common scenario that arises when a user performs a local search for a particular point of interest (for which the results are mapped) and then wishes to examine each point of interest one by one. The conventional approach is for the user to zoom in on a POI, zoom out, then pan to the next POI where the zoom-in zoom-out cycle is repeated. This is inconvenient.
Some rudimentary solutions to this problem involve magnifying only a portion of the map using a virtual magnifying glass. This approach permits the user to view details of the magnified portion at an elevated zoom level while still viewing the rest of the map at its original zoom level. The functionality of these map magnifiers, however, is very limited. Accordingly, improvements on these map magnifier technologies remain highly desirable.
It will be noted that throughout the appended drawings, like features are identified by like reference numerals.